1. Field of the Invention
The present invention relates to dispensers for the delivery of materials in liquid or solution form, and more particularly to such dispensers as are useful in fluid reservoirs having cylic variation in fluid level.
2. Description of the Prior Art
Numerous dispensers are known, that are capable of storing and discharging their contents when placed within fluid reservoirs having cyclic change in fluid level. An example of such a fluid reservoir, is the water tank that is normally associated with the toilet boil of a domestic bathroom toilet apparatus. In such instance, it has long been desirable to dispense a quantity of a cleanser, deodorant or the like, to circulate through the toilet apparatus, to disinfect and clean the walls of the toilet bowl, to maintain the apparatus in hygienic condition.
Representative dispensing devices known in the prior art include the device shown in U.S. Pat. No. 1,002,974 to Dunkley, which shows a reservoir containing a quantity of disinfectant, which is positioned within a larger fluid container or cistern. The disinfectant container has a trough hingeably associated with it, and adapted to alternately scoop up a portion of the fluid in the cistern and transfer it into the disinfectant container. By this means, the disinfectant container is mixed with a quantity of the fluid ambient and, when the total fluid capacity of the disinfectant container is exceeded, a solution containing disinfectant is discharged at the spout.
U.S. Pat. No. 1,227,997 to Clifford discloses a pivoting dispenser adapted to reside within a tank containing a body of fluid, to alternately dispense a quantity of an antiseptic thereinto. The Clifford device utilizes a float such as indicated at 22, which controls the angle and frequency of the tilt of the antiseptic dispenser, and thereby the quantity of fluid released through the nozzle orifice when the dispenser tilts toward the vertical. The Clifford device, however, does not offer the uniform discharge of a premeasured amount of antiseptic, as the amount of discharge will vary with the angle and residence time of the dispenser.
U.S. Pat. No. 2,888,685 to Giangrosso et al discloses a dispenser device for use with a toilet bowl tank that is mountable on the float arm and dispenses a quantity of deodorant when the float arm lowers as the fluid in the tank is drained. This device uses a ball and check valve to permit discharge, which may introduce inaccuracies and nonuniformities in operation. Similarly then, this device cannot assure that a predetermined quantity of deodorant is always dispensed.
Finally, U.S. Pat. No. 4,296,503 to Leardi discloses a dispenser that is mountable within a toilet bowl tank and is adapted to pivot from a floating position to an essentially veritical, dispensing position to discharge a quantity of a deodorant or detergent composition. The Leardi device has an essentially open upper surface that permits unlimited contact with the fluid in the toilet bowl tank with the solid cake of material positioned within the container. The Leardi device shows no means for metering the amount of deodorant or cleaner that will be discharged into the water tank. The consequence of this inability is that the device may discharge an excess of deodorant or cleanser initially, and may thereafter discharge inadequate amounts and ultimately will be totally expended prematurely. As a consequence, the efficiency of operation of the device of Leardi is relatively low.
In similar fashion, those devices in the prior art that appear to offer some metering capability are complex in construction and operation and are correspondingly unreliable. A need therefore exists for the development of a dispensing device that offers simplicity in construction and operation, and reliability of uniformity in the metering of the active ingredient contained therein.